{"paper_id":"07852d9d-fd48-41c9-991d-8f3012070641","body_text":"Abstract\nObjective\nTo study the influence of mifepristone on the expression of cyclooxygenase 2 (COX-2) protein and COX-2 mRNA and then to evaluate the mechanism.\nMethods\nAfter the establishment of 30 mice endometriosis models, the mice were randomly divided into six groups with 5 mice each group and assigned to experimental and control groups of 1-, 4- and 6-week circle according to whether mifepristone (0.13 mg d−1) was taken or not. Small animal optical imaging system was used to detect the fluorescent intensity of the ectopic tissue. Reverse transcript-polymerase chain reaction and western blot was used to examine COX-2 protein and COX-2 mRNA expression. ELISA was used to examine concentration of PGE2 in serum.\nResult(s)\nMifepristone could not affect the fluorescent intensity of the ectopic endometrium after it was taken 1, 4, and 6 (P > 0.05). However, it could decrease the transcription of COX-2 mRNA in the 1 and 4 week groups (P < 0.05), while the difference in the 6 week group was not significant (P > 0.05). It could decrease the expression of COX-2 protein after it was taken 4 and 6 weeks (P < 0.05). The serous PGE2 in the trial groups was lower than that in the control groups, but the difference was not significant (P > 0.05).\nConclusion(s)\nThis study showed that mifepristone could not affect the size of the ectopic endometrium, but it could decrease the transcription of COX-2 gene and then reduce the expression of COX-2 protein and its product PGE2 which is an important factor which mediate pain. This maybe another mechanism that mifepristone takes effect through anti-inflammatory path.\nSimilar content being viewed by others\nReferences\nLampe L (2009) Endometriosis. 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Eur J Pharm Sci 39(5):421–427\nGuo SW, Liu M, Shen F, Liu X (2011) Use of mifepristone to treat endometriosis: a review of clinical trials and trial-like studies conducted in China. Women Health (Lond Engl) 7(1):51–70\nKettel LM, Murphy AA, Morales AJ, Yen SS (1998) Preliminary report on the treatment of endometriosis with low-dose mifepristone (RU 486). Am J Obstet Gynecol 178(6):1151–1156\nConflict of interest\nNone.\nAuthor information\nAuthors and Affiliations\nCorresponding authors\nRights and permissions\nAbout this article\nCite this article\nLi, X., Bao, Y., Fang, P. et al. Effect of mifepristone on COX-2 both in eutopic and ectopic endometrium in mouse endometriotic model. Arch Gynecol Obstet 286, 939–946 (2012). https://doi.org/10.1007/s00404-012-2379-2\nReceived:\nAccepted:\nPublished:\nIssue date:\nDOI: https://doi.org/10.1007/s00404-012-2379-2","source_license":"CC0","license_restricted":false}